A total of 773 adults who'd already lost an average of 11 kilos were assigned to one of five diets each based on a different combination of protein and carbs - some were lower in carbs and higher in protein and vice versa. Some diets included high GI carbs- meaning the 'fast', often more refined carbs that raise and lower blood sugar rapidly; others had slower burning low GI carbs that raise and lower blood sugar more slowly. And the winner? The low GI carb and high protein combo. The people on this diet not only kept the weight off during the six months of the study but they also continued to lose weight too....
There are no fluffy carbs in this diet. Instead it's based on fresh vegetables, lean protein sources like fish, poultry, legumes, nuts and dairy foods and dense, grainy foods like rye bread, pumpernickel and barley - the book's recipe for rye porridge with apple and hazelnuts is the polar opposite of lightweight breakfast cereal.
The reason these robust carbs are more filling than their more refined cousins like white bread isn't just that they keep blood sugar levels steadier, Brand-Miller explains. They also stimulate cells in the gut that produce one of the satiety hormones we need to feel full. These cells are located deep down in the gut – a place that rapidly digested carbs never reach because they're digested in the upper half of the gut, Brand Miller explains.
"This explains why we still feel hungry after we've eaten fluffy white rice," she says.
But while the World's Best Diet is higher in protein and lower in carbs it's no radical diet. The idea is to modestly lower the carbohydrate content of the diet and modestly increase the protein content to give a ratio of around 2:1 in favour of carbs, says Brand- Miller explaining that a typical Australian diet is generally higher in carbohydrates with a ratio as high as 4:1